الفهرس 
Anatomy and Histology of the Vocal FoldsOnly 14 pages are availabe for public view
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Abstract
Polypeptide GFs are a diverse group of hormone-like agents that regulate growth
and differentiation through cell surface receptors. They are generally represented by
homologous families containing several members with distinct overlapping receptor
interactions and hence, responsive tissue specificities. Similarly, their receptors are also
clustered in family groups of sequence-related proteins.
from a functional point of view, polypeptide GFs can conveniently be divided into four
categories:
1. Tissue GFs
2. Hemopoietic GFs
3. Neurotrophic factors
4. Cytokines
There is considerable overlap in the activities of many of these factors and many
can be listed in more than one category. Like most proteins, polypeptide GFs can also
be subdivided into ”families”. This is well illustrated by the IGFs, the FGFs and more
recently, the NGFs.
The primary role of peptide GFs contributes to the fundamental intercellular
signaling within tissues that underlies a complex interaction of cell proliferation,
hypertrophy, migration, differentiation and senescence which proceeds within strict
temporal and anatomical constraints.
FGFs that signal through FGFRs regulate a wide range of biological functions,
including cell proliferation, survival, migration and differentiation. Among the signal
pathways, RAS/MAP kinase is known to be predominant in the case of FGFs.
Organs transplantation or implantation of synthetic devices is the currently
available and most used methods to treat loss of tissues and organs in humans.
However, there is a continue demanding of new solutions and approaches for tissues
failure since the definitive solution is far to be achieved. For this reason, regenerative
medicine and tissue engineering are becoming of great interest as the alternative
strategy to repair or regenerate damaged tissue.
Regenerative medicine provides alternatives to organ transplantation, which is
limited in applicability owing to immune responses against allografts and the large
disparity between the need for organs and tissues and the number available for
transplantation. GFs are critical signaling molecules that instruct cells during
development, and one may achieve tissue regeneration in the adult by enabling control
over GF delivery.
The ideal materials are biodegradable, biocompatible and able to serve as a
supporting artificial ECM until the natural tissue is produced by the neighboring cells as
the biomaterials gradually degrade. The use of GFs has become greatly attractive to
achieve the above mentioned goals, because their activity affect and regulate many
cellular processes involved during tissue healing.
The VF is a multilayered vibrator structure which gives the VFs their
mechanical properties. These structures oscillate during the production of sound.
The SLP is normally very loose and contains abundant interstitial proteins such
as HA, fibronectin and proteoglycans such as fibromodulin, decorin and versican.
In a VF lesion, such as a VF scar, VF sulcus and atrophy, the SLP has deposits
of disorganized thick collagen bundles with little HA. These histological changes induce
VF scarring, vibratory suppression and glottal insufficiency. These changes induce
severe symptoms such as breathy dysphonia, phonasthenia and aspiration associated
with communication disorders and fatal pneumonia.
Various surgical attempts have been performed for these cases; however, a
particular treatment has not been established, because the wound-healing process for
regeneration is unpredictable.
Also UVFP induces not only severe dysphonia but aspiration as well, which
leads to reduction in the patient’s quality of life. Various treatments have been used,
including laryngeal framework surgery and injection laryngoplasty. However, for
patients with mild symptoms of UVFP and individuals with poorer general health, it is
best to receive minimally invasive therapy. Even in severe cases, a six months
observation period is required from onset to laryngeal framework surgery because some
UVFP patients experience spontaneous recovery during their clinical course. Patients
under observation should also receive some type of therapy to mitigate the severity of
dysphonia and aspiration during the observation period. Although various surgical
strategies have been applied in these cases, a definitive treatment has not been
established because these surgical procedures are sometimes performed under general
anesthesia and dysphonia often remain unresolved.
Recent progress in regenerative medicine has made it possible to develop tissue
engineering techniques by using cells, scaffolds, and GFs.
GFs affect cell function, extrinsic application of GFs may induce the
regenerative process. One promising GF is bFGF which is a member of the FGF family
and a promising agent for regenerative medicine of the larynx.
Regenerative treatments using bFGF injection of the SLP of the VFs effectively
improved dysphonia in VF lesions and in UVFP. Cases of severe dysphonia caused by
VF lesions and paralysis were treated by the single bFGF injection method show
significant improvements occurred in MPT, MFR, PR, jitter, SSF and VHI.
The single injection method is easy to perform as an office procedure. The bFGF
is suitable for office procedures because it is less toxic and readily available as an
injectable aqueous solution. Furthermore, bFGF is a type of regenerative medicine that
maintains VF-specific structure, which differs from various foreign material injections.
To summarize the reviewed literature the issue of using bFGF injection to treat
VF lesions and VF paralysis is still controversial and the stage is open for more studies.
Surgical procedures are performed directly on the VFs with the aim of:
1- Closing a phonatory gap causedb by paralytic, sulcus, scar and atrophy.
2- Improving the vibratory movement and restoration of the normal mucosal wave.
3- Correction of VFs position and/or tension.
The objective is to create a common language in order to improve the surgical
description of the procedures proposed by different authors for addressing specific VF
lesions or disorders. This common language will simplify postoperative outcome
comparisons, standardize phonosurgical procedures and facilitate the teaching of
phonosurgery.